QuickTime 4 Reference

QuickTime Vectors and QuickDraw GX

Many of the data structures for QuickTime vectors are derived from data structures for QuickDraw GX, the advanced graphics architecture developed by Apple Computer, Inc. Because of this, many of the identifiers include the prefix "gx". However, you do not need QuickDraw GX to use QuickTime vectors; all its functionality is included in QuickTime. You do need QuickDraw GX or the QuickDraw GX extension to convert existing QuickDraw GX data to QuickTime vector data with the QuickDraw GX transcoder component, as described in "Converting QuickDraw GX Data to QuickTime Vectors" .